Don't assume anything!! I thought I was pulling on the screen connector and I was pulling on an antenna component instead. Didn't ruin its connection range but I sure remember doing it and now my iPad has a little internal flaw only I'm aware of.

I heated mine up for 30 seconds, tested, then again for 30 seconds. It felt adequately hot. Leaving it on the left side, per the instruction, for a minute did not loosen the adhesive. I ended up pulling the suction cup hard enough to shadder the old screen. Moral of the story, I don't think it gets hot enough safely to have an affect.